From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E61FCC433F5 for ; Tue, 16 Nov 2021 13:30:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D10F761B44 for ; Tue, 16 Nov 2021 13:30:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236786AbhKPNdV (ORCPT ); Tue, 16 Nov 2021 08:33:21 -0500 Received: from smtp-out2.suse.de ([195.135.220.29]:38282 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236752AbhKPNdP (ORCPT ); Tue, 16 Nov 2021 08:33:15 -0500 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 8D75C1FCA1; Tue, 16 Nov 2021 13:30:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1637069417; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EhqKr+rTsEmqBNBggfpFhbL56OGP4vni1d1wCyRo57Y=; b=rymaTROeGH/pyQVBNtUZZ4A6YEQsJKKm+0bgDaoQGMCYvLX7XUoYzjqrwrxNZRXMlycuKW kdpu86PEQXgubdrvCNjfcToCW8pVmFutyMOLv1SGR8sAXmhwNYUQLSg0hi6G//+PoidWXe FAUM2/Ga6iYi4jGiMfPn16Rhtomldz4= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1637069417; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EhqKr+rTsEmqBNBggfpFhbL56OGP4vni1d1wCyRo57Y=; b=hhlqvIWuVv9L8+jAEaQkXrsPBgFTZnECcR35/rNdP5aQ3UWSvxsUQ94dXiwi6cVs2zSxDE 8K5I5/v9+eLSFOAA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 417BB13C1B; Tue, 16 Nov 2021 13:30:16 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id u3/dDWiyk2HWfAAAMHmgww (envelope-from ); Tue, 16 Nov 2021 13:30:16 +0000 Date: Tue, 16 Nov 2021 14:30:14 +0100 From: Joerg Roedel To: Sean Christopherson Cc: Marc Orr , "Dr. David Alan Gilbert" , Borislav Petkov , Dave Hansen , Peter Gonda , Brijesh Singh , x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Tom Lendacky , "H. Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , Dov Murik , Tobin Feldman-Fitzthum , Michael Roth , Vlastimil Babka , "Kirill A . Shutemov" , Andi Kleen , tony.luck@intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, Marc Zyngier , Will Deacon , Quentin Perret Subject: Re: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support Message-ID: References: <20210820155918.7518-1-brijesh.singh@amd.com> <061ccd49-3b9f-d603-bafd-61a067c3f6fa@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 15, 2021 at 07:15:07PM +0000, Sean Christopherson wrote: > It creates a new attack surface, e.g. if the guest mishandles the #VC and does > PVALIDATE on memory that it previously accepted, then userspace can attack the > guest by accessing guest private memory to coerce the guest into consuming corrupted > data. If a guest can be tricked into a double PVALIDATE or otherwise misbehaves on a #VC exception, then it is a guest bug and needs to be fixed there. It is a core requirement to the #VC handler that it can not be tricked that way. Regards, -- Jörg Rödel jroedel@suse.de SUSE Software Solutions Germany GmbH Maxfeldstr. 5 90409 Nürnberg Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev